Attachment handling guide

Temporary email can receive attachments—retention depends on the delivery path

Attachments are not ordinary message content. Temporary email lets you view them only while the address is active; forwarding aliases decide whether they also enter a 30-day archive based on size.

Four size thresholds

Check total message size first, then decide whether archiving is needed

Size limits account for the full message and attachment processing overhead. The sender’s own limits may be lower.

Temporary email attachments

View or download them while the current mailbox is active; files are not retained beyond the address lifetime.

Up to 50 MB

The forwarding alias delivers the message normally, with downloads available in the 30-day archive alongside the message details.

50–100 MB

The message is prioritized for delivery to your receiving mailbox, but the archive does not retain a downloadable attachment copy.

Over 100 MB

Rejected to protect the delivery system. Ask the sender to use a trusted cloud-storage link or split the file.

Delivery paths

Three ways an attachment can reach you

“Forwarded” does not necessarily mean “available to download from the archive,” especially for larger attachments.

Temporary inbox

Sender → temporary address → download while active. Best for short-term, low-risk files.

Forward and archive

Sender → alias → regular inbox, with message details and attachment access retained for 30 days.

Forward only

Larger messages go to your regular inbox; the archive only notes that the attachment was not retained, reducing storage exposure.

ConditionDelivered to regular inboxAttachment in 30-day archiveRecommendation
While the temporary address is activeNot applicableNot applicableDownload promptly and verify it yourself
Forwarded message ≤50 MBYesYesStill save necessary files locally
Forwarded message 50–100 MBYesNoDownload from your regular inbox
Forwarded message >100 MBNoNoAsk the sender to use a link or split the file

Safety checklist

Being able to download a file doesn’t mean you should open it

Mailbox isolation can reduce address exposure, but it does not automatically prove that a file is trustworthy.

Verify the sender’s domain

Display names can be spoofed. First confirm that the actual address matches the process you just completed.

Don’t run files directly

Inspect executable files, macro-enabled documents, and unknown archives in a controlled environment first.

Never send secrets

Do not rely on temporary email to transmit or store passwords, recovery codes, identity documents, or private keys.

Save important files elsewhere

A 30-day archive is not a backup service. Save legitimate files you need as soon as possible.